26 



CEEEAL AND FORAGE INSECTS. 



Plats 1, 2, 3, and 4 were examined June 5 and 7, and plats 5 and 6 

 examined June 14. The same plan that was used last year was 

 adopted. The following table gives a brief summary of the results: 



Table II. — Results of experiments in the treatment of seed corn to ward off attacks of the 

 slender seed-corn ground-beetle. 



Plat 

 No. 



Number 

 hills ex- 

 amined. 



Destroyed by 

 Clivina. 



Total. 



Destroyed by other 

 pests. 



Total. 



Per cent 

 affected 



by 

 Clivina. 



Per cent 



affected 



by other 



pests. 



Number 

 hills en- 

 tirely de- 

 stroyed. 



Number 



hills 



with only 



1 plant. 



Number 

 hills en- 

 tirely de- 

 stroyed. 



Number 



hills 



with only 



1 plant." 



1 

 2 

 3 

 4 

 5 

 6 



200 

 200 

 200 

 200 

 95 

 93 



8 

 20 

 17 

 5 

 5 

 5 



10 

 14 

 18 

 16 

 7 

 11 



18 

 34 

 35 

 21 

 12 

 1G 





46 

 24 

 24 

 13 

 9 

 10 



46 

 24 

 24 

 13 



12 

 18 



9 



17 



17.5 

 10.5 

 12.6 

 17.4 



23 

 12 

 12 

 6.5 

 12.6 

 19.3 









3 



8 



The last two plats (5 and 6) should not have been planted until 

 about June 10. Normal results could not be expected from such 

 small plantings, as the beetles were no longer working on the larger 

 corn ; consequently the percentage of beetles to the hill in these plats 

 must necessarily have been much larger than in the early plantings, 

 when the whole field was planted at once. 



In plats 2 and 3 it will be noted that 20 and 17, respectively, are 

 the number of hills mentioned as being entirely destroyed by the 

 Clivina. In both of these plats were found hills that contained no 

 seed, and, as no other cause for this could be assigned, the whole was 

 charged up to the Clivina. 



Three checks near the plats were examined, counts being made of 

 the number of hills with only one plant. None of these hills was dug 

 up, as Mr. Baker had replanted the corn, and, of course, this would 

 have interfered with the results. 



The following table gives the results of counts in these check areas : 



Table III. — Results of examination of check areas of corn as to injury from the slender 



seed-corn ground-beetle. 



Check number. 



Number 

 hills ex- 

 amined. 



Number 

 hills with 

 plants 

 entirely 

 missing. 



Number 



hills with 



only 1 



plant. 



Total per 

 cent of 



hills 

 affected. 



1 



200 

 200 

 200 



24 

 20 

 17 



44 

 36 

 46 



34 



2 



28 



3 



31.5 







